Effects of ultrasound on cross-flow ultrafiltration of skim milk: Characterization from macro-scale to nano-scale

Y. Jin (1) , S. Baup (1) , N. Hengl (1) , F. Pignon (1) , N. Gondrexon (1) , M. Sztucki (2) , Geneviève Gésan-Guiziou (3) , A. Magnin (1) , M. Abyan (1) , M. Karrouch (1) , D. Blèsès (1)

1 LRP - Laboratoire Rhéologie et Procédés
2 ESRF - European Synchrotron Radiation Facility
3 STLO - Science et Technologie du Lait et de l'Oeuf

This studyinvestigateseffectsofultrasound(US)oncross-flow ultrafiltration ofskimmilkbymulti-scale characterization,usingacustomdesigned “SAXS Cross-FlowUS-coupledFiltrationCell”. Thestudyof flow propertiesofcaseinmicellesuspensionsshowsanevolutionoftheirrheologicalbehaviorfrom Newtoniantoshear-thinninguntiltheemergenceofyieldstresswiththeincreaseofconcentration (from 27gL 1 to 216gL 1). Theconcentrationprofiles duringcross-flow filtration ofskimmilkhave been revealedforthe first timebyreal-time in-situ Small AngleX-rayScattering(SAXS)measurement. Without anychangeofinternalstructureofcaseinmicellesandmembraneselectivity,theapplied ultrasound (20kHz,2Wcm 2) leadstoasignificant increaseofpermeate flux arisingfromadisruption of concentratedlayer.VaryingtheUSintensityfrom0.6Wcm 2 to 2.9Wcm 2 does notaffecttheUS enhancement factor,whichhoweverdependsonthefeedconcentration.Infact,increaseoffeed concentration inducestheformationofhighlycohesivefoulinglayerduring filtration thattheappliedUS could hardlydisrupt.ResultsalsosuggestthatthepreventiveUSapplicationmodeispromisingsince formation ofthereversiblefoulinglayerwasstronglylimitedinthismode.

Mots clés: membrane; technologie laitière; micelle de caséine; ultrason; ultrafiltration; lait

Domaines: Ingénierie des aliments; Alimentation et Nutrition; Génie des procédés

Y. Jin, S. Baup, N. Hengl, F. Pignon, N. Gondrexon, et al.. Effects of ultrasound on cross-flow ultrafiltration of skim milk: Characterization from macro-scale to nano-scale. Journal of Membrane Science, 2014, 470, pp.205-218. ⟨10.1016/j.memsci.2014.07.043⟩. ⟨hal-01209710⟩